1. Something that has been or is worthy of being thrown away or discarded; that which may be squandered. Also: an act of throwing away, discarding, or squandering something.

1870 J. LukinAmateur Mechanic's Workshop 104
You will find yourself buying a new lathe of better quality, and the first will be seen to have been a throw-away of money.

1911 Sat. Evening Post 22 Apr. 59
(advt.)
Hundreds of articles which you now throw away as ruined, can be made like new... Send for a book that tells how to get value out of your household throwaways.

1955 N.Y. Times 29 May vi. 15/1
Generally, the program opens with a line of girls in two or three minutes of fast-stepping, high-kicking precision dancing. This is a throwaway, designed to get late-comers settled into their seats before the real show starts.

1987 J. ShawCloseups in Nature 16/1
One person's photographic jewels may be another person's throwaways.

2003 J. Morris in Times 14 May (Everest section) 12/2
They look like groups of gentlemanly ruffians, dressed in apparent throwaways, old army jerseys, battered trilby hats.

3.U.S. A person who has been abandoned; esp. a child or teenager thrown out or forced out of his or her home. Sometimes contrasted with runawayn. 1a.

1969 L. A. RichetteThrowaway Children v. 100
I too was filled with sadness—for him and all the other throwaways who are cheated out of childhood.

1991 Urban Anthropol.20 196
Many of the teens whose interviews reveal that they have..slept in cars, and sometimes gone to shelters or other institutional settings, are runaways or throwaways from very difficult family situations.

a. Of a line or speech, remark, etc.: trivial, insignificant; (also) delivered in a casual way; understated or played-down, often for increased dramatic effect.

1956 Time & Tide 25 Feb. 198/3
I am an assiduous collector of those valuable ‘throw-away’ jokes which can be used to brighten up speeches.

1993 Times 31 July (Mag. section) 24/4
We are amused, surprised, outraged, or simply stunned by the perfectly crafted throw-away remarks which propel the horrible plot.

2009 L. PapadopoulosWhat Men say, what Women Hear i. 12
A throwaway comment from your ex-boyfriend about how he's not really into blondes turns into My hair looks bad, and if he thinks so, so will every other guy.

b. Characterized by understatement; casual or understated in style or technique.

1958 M. DickensMan Overboard vii. 102
He was more cunning than he seemed with that throw-away sixth-form voice.

1962 Times 1 May 15/1
One act, the Temperance Seven, is very good, but their technique in their half-comic, wholly loving re-creations on 1920s popular music is too throwaway, too underplayed to storm an audience's sympathies.

1972 Daily Tel. 29 June 7/7
You can carry your enthusiasm..into casual slouchy nonchalance, and the outstanding collection of Stephen Adnitt had plenty of this throwaway chic.

2014 S. Zagorski-ThomasMusicol. Record Production v. 80
Cocker's timbre gives the impression of a throwaway delivery and a world-weary lack of effort.